Iterative joint tone-interference cancellation and decoding for MIMO-OFDM

In this paper, multi-input multi-output orthogonal frequency-division multiplexing (MIMO-OFDM) is considered under the effects of both multipath fading and multi-tone interference (MTI). The MIMO-OFDM system makes joint use of channel and orthogonal space-frequency block coding (OSFBC) on the transmit side and iterative processing on the receiver side for robustness and improved performance against the fading and MTI effects of the channel. The new iterative receiver is implemented by either an optimal a posteriori probability (APP) space-frequency detector (SFD) or a soft information-aided minimum mean-squared error (MMSE) combiner at its front-end and a soft input-soft output (SISO) channel decoder at its back-end. Both receivers are compared in terms of their computational complexities and bit-error rate (BER) performances. Both iterative receivers provide a improvement in performance after only a few detection/decoding iterations. Also, despite its subopti-mality, the MMSE receiver achieves a BER performance close to that of the APP detector at a significantly lower cost.